The secret communications between bin Laden and Atiyah Abd al Rahman, aka Sheikh Mahmud, have been released in evidence in a US terrorism trial and also reveal the extent of the Jihadis’ concern about espionage and surveillance.

They were discovered at bin Laden’s home in Abbottabad, northern Pakistan, following the US Navy Seals raid in May 2011.

One letter from Mahmud gives a detailed description of a May 2010 drone strike in North Waziristan that killed al Qaeda finance chief, Mustafa abu al Yazid. According to Mahmud, Yazid was with family members at the time of the strike. They were sleeping in the house of a prominent al Qaeda supporter.

The victims included Yazid’s Egyptian wife Umm al Shaymah, three of their daughters and a granddaughter named Hasfah. Another daughter, Umm Hasfaeh Al Shayma, was injured but survived. The strikes also killed the youngest son of another al Qaeda member, Abu Tariq al Tunisi and the owners of the home.

The names of Umm al Shaymah and Hasfah have been added to the list of drone victims being compiled by the Bureau’s Naming The Dead project.

Mahmud wrote that Yazid had not planned to spend the night in the house, and that less than hour before his death, his son had arrived to move him to another location. Finding his father asleep, the son decided to leave him be.

Mustafa Abu Yazid, from al Qaeda propaganda.

The documents relate how another strike killed 20 members of al Qaeda’s Abu Bakr al Sidiq Brigade. Mahmud told bin Laden the men had gathered for Eid celebrations in defiance of al Qaeda orders restricting any gathering to five or fewer people. The victims, Mahmud wrote, included two Iranian Kurds, three Libyans, two or three from the Arabian Peninsula and a number of Turks.

Critics of the Bureau’s work have argued that its method of compiling open source data does not result in reliable accounts of the US drone campaign. In fact the new documents corroborate much of what the Bureau has published.

The new documents show that in two cases – Ob94 and Ob101 – the Bureau accurately identified the big name targets.

[pullquote] “Our bothers and other Pashtun security units are constantly uncovering and destroying spies’ networks… That has not kept airstrikes from hitting us repeatedly because we continue to make mistakes.“

– Atiyah Abd al Rahman [/pullquote]

The Bureau’s method of reporting strikes allows the incorporation of conflicting accounts. No account of a strike is considered closed and all entries in the drone database are revised when new information comes to light.

Before the new documents became available, the Bureau’s reporting of Ob94 cited numerous contemporaneous news reports that said up to 10 civilians died. An al Qaeda press release issued shortly after the attack said 6 civilians had died. The internal al Qaeda documents show the figure “6” referred to civilians who were close relations of Al Qaeda fighters.

The new documents have helped get a fuller picture of another strike. The Bureau’s report of Ob161 stated that a total of 20 people were killed including 0-9 civilians. The papers submitted to the US court suggest that the “0” figure is the correct one: “They were all militant Mujahadeen from one of our Brigades,” the al Qaeda document said.

The documents mention three other victims of drone strikes. There is a reference to “al Sadi (Ihsanullah)” being killed by an air attack around 12 June 2010. That matches the Bureau’s report of strike Ob97. And in October or November 2010 two men, Muhammad Khan and Muawiyah al Balushi, were killed together by one of the many strikes during this period. The documents suggest al Balushi was being considered for the task of moving bin Laden’s son Hamzah to a safe place.

Fatima in hospital before she died in Ob94. She perished with her mother and sister Nisa, along with Abu Yazid and his family (Photo: Noor Behram)

Muhammad Khan and Muawiyah al Balushi have been added to the list of drone victims being compiled by the Bureau’s Naming The Dead project.

As well as providing detailed information about particular strikes, the documents give more general insights into the drone campaign and its impact on al Qaeda. There are frequent references to the extent to which al Qaeda’s activities were disrupted by drones and their associated spy networks.

Much of the information used to identify drone targets is thought to come from human intelligence sources working for the US.

Mahmud complained that most of al Qaeda’s problems were due to spies resulting in “grave shortages in personnel” at all levels. The espionage war he wrote, “has really taken its toll on us”. He told bin Laden: “Our bothers and other Pashtun security units are constantly uncovering and destroying spies’ networks.” But, he added: “That has not kept airstrikes from hitting us repeatedly because we continue to make mistakes…”

The documents show that, because of the strikes, al Qaeda members were forced to concentrate on defensive security and survival. Al Qaeda counter measures – some proposed and some acted upon – included stopping operations so as to reduce the need for movement; trying to hack into the drones (without success); relocating senior members away from Pakistan and reducing media appearances so as to make the organisation less conspicuous.

A previous batch of bin Laden documents released to the Combating Terrorism Center in the US military academy West Point revealed that drones had long worried Bin Laden. He instructed his followers to stop using cars and to not meet on roads. He also warned supporters that the Americans had methods of identifying houses that were frequented by men at a higher rate than usual.

Bin Laden ordered that when al Qaeda received ransom money it be exchanged into a different currency in case the notes had been marked and could be seen from the sky.

Al Qaeda’s fear of surveillance became so great that when one of bin Laden’s wives was being moved from Iran to Abbottabad there was concern about a dental filling she had done in Iran. Bin Laden’s son Hamzah raised the possibility that the filling contained some sort of tracking device.